[Technical Field]
[0001] The present invention relates to an acicular body, and more specifically, a fine
acicular body which is applied onto the skin so as to pierce the skin.
[0002] The present application claims priority to Japanese Patent Application No.
2013-151797 filed on July 22, 2013, the contents of which are incorporated herein by reference.
[Background Art]
[0003] A percutaneous absorption method, which is a method for allowing a substance such
as drug to penetrate through the skin to be delivered into the body is used as a convenient
way of painless administration of the substance to be delivered.
[0004] In the field of percutaneous administration using a percutaneous absorption method,
a technique has been proposed in which an acicular body having a needle which is sized
in the order of micro-meters is used to pierce the skin, thereby administering a substance
such as a drug into the skin (see PTL 1).
[0005] A method for manufacturing the acicular body has been proposed, in which an original
plate is manufactured by machine processing, the original plate is used to fabricate
a transfer plate, and the transfer plate is used for transfer molding (see PTL 2).
[0006] Another method for manufacturing the acicular body has been proposed, in which an
original plate is manufactured by etching, the original plate is used to fabricate
a transfer plate, and the transfer plate is used for transfer molding (see PTL 3).
[0007] The acicular body is preferably made of a material that is harmless to the body even
if a broken piece of the acicular body remains in the body. Accordingly, biocompatible
materials such as chitin and chitosan are proposed as materials for the acicular body
(see PTL 4).
[0008] Further, when the acicular body is used for piercing the skin, it is preferable to
use an adhesive material in order to prevent the acicular body from falling off from
the skin.
[Citation List]
[Patent Literature]
[Summary of the Invention]
[Technical Problem]
[0010] The acicular body which uses a biocompatible material made of water-soluble polymer
such as chitosan, hydroxypropyl cellulose or collagen can dissolve in the skin after
it is pierced into the skin. Accordingly, the acicular body can be manufactured to
contain a substance to be delivered into the skin along with the water-soluble polymer
so that the substance is delivered in the skin as the water-soluble polymer dissolves
after the acicular body is pierced into the skin.
[0011] Further, an acicular body which uses a thermoplastic resin such as polycarbonate,
cyclic olefin copolymer, polylactic acid or polyglycolic acid can be manufactured
with the surface of the acicular body being coated with a solution of substance to
be delivered so that the substance is delivered in the skin after it is pierced into
the skin.
[0012] In piercing the acicular body into the skin, an adhesive material is preferably provided
on the surface of the acicular body to improve adhesion to the skin. A colorless transparent
adhesive is used to improve the appearance of the acicular body pierced into the skin.
[0013] However, there is a problem that, when the acicular body formed of a combination
of a colorless transparent adhesive and a substantially colorless transparent acicular
body made of hydroxypropyl cellulose or the like is pierced into the skin and then
peeled off from the skin after dissolution of the acicular body, a clinician or a
patient can not easily confirm by visual observation to what extent the needles remain
on the acicular body which has been peeled off from the skin and thus whether the
needles will be sufficiently dissolved in the skin or not.
[0014] In light of the above circumstances, the present invention has an object of providing
an acicular body which allows for easy visual observation of the appearance of the
needle.
[Solution to Problem]
[0015] An acicular body according to an aspect of the present invention includes a support
plate having a brightness of 5.0 or less; and a needle disposed on the support plate,
the needle including a tip which is formed so as to pierce the skin and a light transmission
area which is located in an area containing the tip and has a total light transmittance
of 20% or more.
[0016] The needle according to an embodiment of the present invention may be made of a chitosan
derivative.
[0017] The needle according to an embodiment of the present invention may be made of a water-soluble
material.
[0018] The needle according to an embodiment of the present invention may include a base
portion having a surface which faces a surface of the support plate.
[0019] The support plate according to an embodiment of the present invention may include
a projection formed at a position which corresponds to the needle.
[0020] The support plate according to an embodiment of the present invention may be made
up of a transparent adhesive layer and a colored base material tape.
[0021] The support plate according to an embodiment of the present invention may include
a colored base material tape and a transparent adhesive layer disposed on the base
material tape.
[Advantageous Effects of Invention]
[0022] According to the above aspect of the present invention, the appearance of the needle
can be easily confirmed by visual observation.
[Brief Description of the Drawings]
[0023]
[Fig. 1] Fig. 1 is a schematic view which shows an acicular body according to one
embodiment of the present invention.
[Fig. 2A] Fig. 2A is a perspective view which shows a modified example 1 of the acicular
body according to one embodiment of the present invention.
[Fig. 2B] Fig. 2B is a sectional view which shows the modified example 1 of the acicular
body according to one embodiment of the present invention.
[Fig. 3A] Fig. 3A is a perspective view which shows a modified example 2 of the acicular
body according to one embodiment of the present invention.
[Fig. 3B] Fig. 3B is a sectional view which shows the modified example 2 of the acicular
body according to one embodiment of the present invention.
[Fig. 4A] Fig. 4A is a perspective view which shows a modified example 3 of the acicular
body according to one embodiment of the present invention.
[Fig. 4B] Fig. 4B is a sectional view which shows the modified example 3 of the acicular
body according to one embodiment of the present invention.
[Fig. 5A] Fig. 5A is a perspective view which shows a modified example 4 of the acicular
body according to one embodiment of the present invention.
[Fig. 5B] Fig. 5B is a sectional view which shows the modified example 4 of the acicular
body according to one embodiment of the present invention.
[Fig. 6A] Fig. 6A is a perspective view which shows a modified example 5 of the acicular
body according to one embodiment of the present invention.
[Fig. 6B] Fig. 6B is a sectional view which shows the modified example 5 of the acicular
body according to one embodiment of the present invention.
[Fig. 7A] Fig. 7A is a side view of the acicular body according to one embodiment
of the present invention before the acicular body is applied on the skin.
[Fig. 7B] Fig. 7B is a top view of the acicular body according to one embodiment of
the present invention before the acicular body is applied on the skin.
[Fig. 7C] Fig. 7C is a side view of the acicular body according to one embodiment
of the present invention after the acicular body is applied on the skin.
[Fig. 7D] Fig. 7D is a top view of the acicular body according to one embodiment of
the present invention after the acicular body is applied on the skin.
[Fig. 8A] Fig. 8A is a side view of the conventional acicular body before the acicular
body is applied on the skin.
[Fig. 8B] Fig. 8B is a top view of the conventional acicular body before the acicular
body is applied on the skin.
[Fig. 8C] Fig. 8C is a side view of the conventional acicular body after the acicular
body is applied on the skin.
[Fig. 8D] Fig. 8D is a top view of the conventional acicular body after the acicular
body is applied on the skin.
[Fig. 9] Fig. 9 is a microscope image of the acicular body of an example of the present
invention taken from the needle-side.
[Fig. 10] Fig. 10 is a microscope image of the acicular body of a comparative example
taken from the needle-side.
[Description of Embodiments]
[0024] With reference to Figs. 1 to 3B, an acicular body according to one embodiment of
the present invention will be described. First, a configuration of the acicular body
manufactured in the present embodiment will be described.
[0025] An acicular body 1 of the present embodiment includes a support plate (base) 10 and
needles 20 (light transmission areas 20c) formed on the support plate 10.
[0026] The support plate 10 supports the needles 20 and may be formed by a film made of
resin or the like. The material of the film member used for the support plate 10 is
not specifically limited, and may be, for example, cellophane, polyethylene, polypropylene
or polyimide.
[0027] The needle 20 is made of a material which dissolves after it is pierced into the
skin. The needle 20 may be made of a material such as water-soluble polymer or disaccharide.
The needle contains a desired substance to be delivered which is mixed or applied
so that the substance to be delivered is percutaneously introduced in the body when
the needle dissolves in the skin.
[0028] Water-soluble polymers which can be used as a material for the needle may include
carboxymethyl cellulose (CMC), methylcellulose (MC), hydroxypropyl cellulose (HPC),
hydroxypropyl methylcellulose (HPMC), polyvinyl alcohol (PVA), polyacrylic acid polymer,
polyacrylamide (PAM), polyethylene oxide (PEO) and the like. Since the needle 20 is
made of water-soluble polymer, a user can visually recognize that the needle disappears
after the acicular body is applied. This improves the user's ease of use.
[0029] Disaccharides which can be used as a material for the needle may include sucrose,
lactulose, lactose, maltose, trehalose, cellobiose and the like. Particularly, trehalose
which is a disaccharide is preferably used. When a substance to be delivered is a
protein, trehalose protects and stabilizes the protein since trehalose has a crystal
structure similar to that of water.
[0030] In addition to that, starch, chitosan, as well as chitosan derivative such as chitosan
succinamide can be used. Hereinafter, those may be collectively referred to as "needle
material".
[0031] Among the above described needle material, chitosan, chitosan succinamide, HPC and
CMC are particularly preferable as a material for needle since they are biologically
highly safe. The material for needle in the acicular body of the present embodiment
is not limited to a specific material and may be any material that dissolves after
it is pierced into the skin.
[0032] Each needle 20 may be in any shape as long as it can pierce the skin, and may be
selected from various shapes such as cone, pyramid, cylinder, prism and pencil-like
shape (a shape having a column body and a cone-shaped tip portion).
[0033] A single needle 20 may be provided on the support plate 10, or alternatively, a plurality
of needles 20 may stand closely together on the support plate 10. When a plurality
of needles 20 stand, the needles 20 are preferably arranged in array. The term "array"
as used herein means that the needles are arranged in a specific pattern such as a
matrix arrangement, a close-packed arrangement, a concentric circle arrangement and
a random arrangement.
[0034] Further, Fig. 1 shows an example in which a plurality of needles 20 are integrally
formed with a base portion 20b (needle) supported by the support plate 10. In the
present embodiment, as shown in the modified example 1 of Figs. 2A and 2B, the respective
needles 20 may be independently formed on the support plate 10 instead of the needles
20 integrally formed with the base portion 20b. Further, as shown in the modified
example 2 of Figs. 3A and 3B, a plurality of needles 20 may be independently formed
spaced from each other instead of the needles integrally formed with the base portion.
In this configuration, as shown in Figs. 3A and 3B, the support plate may include
projections 10b formed at positions which correspond to the needles 20.
[0035] A hole may be formed at the tip of the needle 20. The hole may or may not penetrate
through the support plate 10 in a thickness direction.
[0036] The needle 20 preferably has thickness and length suitable for creating a puncture
hole into the skin. Specifically, the needle 20 preferably has a height H in the range
of 10 µm to 1000 µm. The height H refers to a length from a surface of the support
plate 10 to a tip of the needle 20.
[0037] The height H of the needle 20 may be determined within the above range depending
on a desired depth of the puncture hole made by the acicular body piercing the skin.
[0038] For example, when a puncture hole made by the acicular body 1 piercing the skin is
desired to be within the stratum corneum, the height H is preferably in the range
of 10 µm to 300 µm, and more preferably, in the range of 30 µm to 200 µm.
[0039] Alternatively, when a puncture hole is desired to have a depth that penetrates through
the stratum corneum and does not reach the nerve plexus, the height H is preferably
in the range of 200 µm to 700 µm, more preferably, in the range of 200 µm to 500 µm,
and further preferably, in the range of 200 µm to 300 µm.
[0040] When a puncture hole is desired to have a depth that reaches the dermis, the height
H is preferably in the range of 200 µm to 500 µm.
[0041] Alternatively, when a puncture hole is desired to have a depth that reaches the epidermis,
the height H is preferably in the range of 200 µm to 300 µm.
[0042] The needle 20 preferably has a width D in the range of 1 µm to 300 µm. The width
D may be determined within the above range depending on a desired depth of the puncture
hole made by the acicular body piercing the skin.
[0043] The width D is a maximum dimension of a portion of the needle which is in contact
with the support plate when the needle is projected in parallel to a plane of the
support plate 10. For example, when the needle is a conical or columnar shape, the
width D is the diameter of the circular portion of the needle which is in contact
with the support plate. When the needle is a regular quadrangular pyramid shape or
regular quadrangular prism shape, the width D is the diagonal length of the square
portion of the needle which is in contact with the support plate.
[0044] The needle 20 preferably has an aspect ratio in the range of 1 to 10. An aspect ratio
A is defined as A = H/D, where H is a height and D is a width of the needle.
[0045] When the needle 20 has a tip angle of a cone-shaped portion and is used to penetrate
through the stratum corneum, the tip angle θ of the needle is preferably in the range
of 5 to 30 degrees, and more preferably, in the range of 10 to 20 degrees. The tip
angle θ is a maximum angle (apex angle) when the needle 20 is projected in parallel
to a plane of the support plate 10.
[0046] The substance to be delivered contained in the needle 20 may include various proteins,
pharmacological active agents, cosmetic compositions and the like.
[0047] Pharmacological active agents may be selected as appropriate depending on the applications.
For example, vaccines against influenza, analgesics for cancer patients, insulins,
biologic agents, gene therapy agents, injection agents, oral agents or skin applying
agents may be used. Since the acicular body according to the present invention pierces
the skin, it can be applied to pharmacological active agents which need to be administered
by subcutaneous injection besides the pharmacological active agents used for the conventional
percutaneous administration. In particular, since injection agents such as vaccines
can be administered painlessly by using the acicular body, the acicular body is suitable
for use with children. Further, children have difficulty in swallowing an oral medication
in the conventional way of administration. Since there is no need for swallowing a
medication if the acicular body is used for drug administration, the acicular body
is suitable for use with children.
[0048] The cosmetic compositions are compositions used for cosmetics or beauty products.
For example, they may include moisturizing agents, coloring materials, fragrances,
and biologically active substances that express beauty effects (beneficial effects
for wrinkles, acne, stretch marks and the like, and mitigating effect on hair loss).
When an aromatic material is used as a cosmetic composition, favorable fragrance can
be added to the acicular body. This is suitable for use as a beauty product.
[0049] The needle 20 is formed to be transparent or translucent and has total light transmittance
of 20% or more. Accordingly, the color of the support plate 10 can be visually observed
via the needle 20.
[0050] The support plate 10 has a color having a brightness of 5.0 or less. As long as the
support plate 10 has a brightness of 5.0 or less, hue and saturation are not specifically
limited.
[0051] Since the total light transmittance of the needle 20 and the brightness of the support
plate 10 in the acicular body 1 of the present embodiment are defined as described
above, the needle 20 can be visually observed with ease when the needle 20 is seen
from a position on the side of the needle 20 with the needle 20 overlapping the support
plate 10 by virtue of the color of the support plate 10 which can be visually observed
via the needle 20.
[0052] An example of manufacturing method of the acicular body 1 having the above configuration
will be described.
[0053] First, an intaglio plate used for forming the needle is prepared. The original plate
that defines the shapes of a plurality of needles 20 is manufactured. Then, the intaglio
plate is manufactured by inverting the shapes of protrusions and recesses of the original
plate. The original plate may be manufactured by a known method depending on the shapes
of the needles, and may be manufactured by using micromachining technique. Examples
of micromachining technique may include lithography, wet etching, dry etching, sandblasting,
laser machining and precision machining. The intaglio plate may be manufactured by
a known transfer molding method by using the original plate. For example, the intaglio
plate made of Ni may be manufactured by Ni electroforming method, or the intaglio
plate may be manufactured by transfer molding using melted resin.
[0054] With the procedure described above, the intaglio plate having the recesses which
correspond to the needles 20 are formed.
[0055] Then, a needle-forming solution containing a needle material which is appropriately
selected is prepared. The needle-forming solution preferably has a fluidity of such
an extent that allows it to be suitably filled in the recesses of the intaglio plate
by adjusting the amount of solute as appropriate, and the needle-forming solution
may be in the form of gel. The total light transmittance of the needle is decided
by adjusting the concentration and the like of the needle material in the needle-forming
solution.
[0056] Then, the needle-forming solution is supplied onto the intaglio plate. A supplying
method can be appropriately selected from known methods, taking into consideration
the shape or dimensions of the intaglio plate. For example, methods such as spin coating
method, method using a dispenser, casting method and ink-jet method can be used. Although
the needle-forming solution may be supplied to the intaglio plate under an ordinary
pressure, the needle-forming solution may also be supplied under a reduced pressure
or vacuum pressure in order to perform more advantageous filling of the recesses.
Preferably, the amount of the needle-forming solution is such an extent that allows
it to cover all the recesses.
[0057] Then, the liquid component is removed from the needle-forming solution, and the needle-forming
solution is solidified to form the needles.
[0058] This process can be performed by drying the needle-forming solution while holding
the intaglio plate under a room temperature. Preferably, the needle-forming solution
is heated and dried by heating the intaglio plate in order to shorten the required
time. Heating method is not specifically limited, and, for example, a hotplate can
be used so that the intaglio plate is placed thereon.
[0059] After the needles 20 are formed, the support plate 10 having a predetermined brightness
is placed on the intaglio plate. An adhesive layer or the like is disposed on the
surface of the support plate 10 so that the needles 20 are adhered to the support
plate 10. When the support plate 10 is peeled off from an intaglio plate 30, the needles
20 are removed along with the support plate 10 from the intaglio plate 30. Accordingly,
the acicular body 1 having the support plate 10 and the needles 20 are manufactured.
[0060] The intaglio plate 30 may be chemically dissolved instead of being peeled off as
described above so as to separate the needles 20.
[0061] After completion of the acicular body 1, the acicular body 1 may be punched out to
form a desired size and shape according to the application. A punching blade such
as Thomson blade may be used for punching. Alternatively, the acicular body 1 may
be punched out along with the intaglio plate before the support plate 10 is peeled
off from the intaglio plate.
[0062] An adhesive may be applied on the periphery of the needles to provide an acicular
body that can be applied as a patch on the skin or the like. An adhesive is preferably
made of a material suitable for skin patching, and is further preferably made of a
material that can be treated by a sterilization process.
[0063] The above manufacturing method is merely an example, and various modifications can
be made. For example the support plate 11 as shown in Figs. 4A and 4B may be formed
by disposing a colored material which is made by adding a pigment to the needle-forming
solution on the intaglio plate in the form of layer and solidifying it in the same
manner as the needle 20, which does not need to use a colored film as the support
plate. In this configuration, although part of the needle 20, for example, the base
portion 20b may be colored as shown in Figs. 4A and 4B, at least a portion having
the tip 20a which is pierced into the skin (the light transmission area 20c including
the tip 20a) has the above total light transmittance. Further, in the above embodiment,
the acicular body is described as including the support plate formed by a colored
film. Alternatively, as shown in Figs. 5A and 5B, the transparent or translucent needles
and the transparent or translucent base portion may be fixed on the colored support
plate 40 such as an adhesive tape. Alternatively, as shown in Figs. 6A and 6B, the
transparent or translucent needles and the transparent or translucent base portion
may be fixed on the support plate 60 such as an adhesive tape made up of a transparent
adhesive layer 12 and a colored base material tape 50. In measurement of the brightness
of the support plate 60 shown in Figs. 6A and 6B, the brightness of the surface of
the base material tape 50 which faces the transparent adhesive layer 12 may be measured.
[0064] According to the acicular body 1 of the present embodiment, since the total light
transmittance of the needle 20 and the brightness of the support plate 10 are defined
as described above, a user can visually observe the needle 20 disposed on the support
plate 10 with ease. Accordingly, in applying the acicular body 1 on the skin, the
needle 20 can be reliably applied at an intended position. Further, when the acicular
body 1 is peeled off from the skin, the state of the needle 20, for example, whether
the needle remains or not can be easily observed. As a result, the effect of the acicular
body and the state of delivery of the substance to be delivered can be accurately
recognized, thereby improving the effect and ease of use.
[0065] With reference to Figs. 7A to 8D, the effect of the present invention will be described.
[0066] Figs. 7A to 7D are explanatory views of the acicular body 1 according to the present
embodiment. Fig. 7A is a side view of the acicular body before the acicular body is
applied on the skin. Fig. 7B is a top view of the acicular body before the acicular
body is applied on the skin. Fig. 7C is a side view of the acicular body after the
acicular body is applied on the skin. Fig. 7D is a top view after the acicular body
is applied on the skin.
[0067] While Figs. 7A to 7D show the effect obtained by the acicular body according to one
embodiment, the same effect can be obtained by a configuration which uses the above
support plates 11, 40 and 60 instead of the support plate 10.
[0068] Figs. 8A to 8D are explanatory views of the conventional acicular body 100 which
includes the needle 101 and the support plate 102. Fig. 8A is a side view of the acicular
body before the acicular body is applied on the skin. Fig. 8B is a top view of the
acicular body before the acicular body is applied on the skin. Fig. 8C is a side view
of the acicular body after the acicular body is applied on the skin. Fig. 8D is a
top view of the acicular body after the acicular body is applied on the skin.
[0069] According to the acicular body 1 of the present embodiment, a portion in the vicinity
of the tip of the needle 20 can be seen brightly and clearly and is visually observed
as shown in Fig. 7B. Accordingly, in applying the acicular body 1 on the skin, the
needle 20 can be reliably applied at an intended position. Further, in observation
of the acicular body after it is peeled off from the skin, the vicinity of the tip
of the needle is not seen brightly any more as shown in Fig. 7D when the tip of the
needle does not remain. Accordingly, a user can easily recognize that the needle tip
has been dissolved by comparing the state before use which is shown in Fig. 7B and
the state after being peeled off from the skin which is shown in Fig. 7D.
[0070] On the other hand, in the conventional acicular body, it is difficult to visually
observe the portion in the vicinity of the tip of the needle 101 as shown in Fig.
8B compared with that shown in Fig. 7B. Accordingly, in the conventional acicular
body, a user can not easily recognize that the needle tip has been dissolved since
the difference between the state before use which is shown in Fig. 8B and the state
after being peeled off from the skin which is shown in Fig. 8D is not readily understandable.
[0071] The acicular body of the present invention will be further described with reference
to examples and comparative examples. However, the present invention is not limited
in any way to these examples and comparative examples.
(Example 1)
(Manufacturing of intaglio plate)
[0072] An original plate for the acicular body was formed by micromachining a silicon substrate
so that 36 regular quadrangular pyramids (height: 150 µm, bottom: 60 µm × 60 µm) were
arrayed in a matrix of 6 rows by 6 columns with a pitch of 1 mm. The acicular body
original plate was coated with a nickel film by plating in the thickness of 500 µm.
Then, the silicon substrate was wet-etched with potassium hydroxide solution of weight
percent concentration of 30% which was heated to 90°C. Accordingly, an intaglio plate
made of nickel and having 36 recesses which correspond to the shape of the needles
was manufactured.
(Preparation of needle-forming solution)
[0073] Chitosan succinamide, which was a chitosan derivative, was dissolved in water to
prepare chitosan succinamide solution of weight percent concentration of 5% (5 wt%).
(Manufacturing of needle)
[0074] A spin coating method was used to fill the recesses of the intaglio plate with the
needle-forming solution. Then, the needle-forming solution was further supplied to
such an extent that a layer was formed on the intaglio plate. The intaglio plate was
heated at a temperature of 120°C for a period of 10 minutes by using a heat source
so that the needle-forming solution was dried and solidified. A hotplate was used
as the heat source.
[0075] After the solidifying process, the needle-forming solution which was solidified in
the form of layer was held and removed from the intaglio plate to manufacture a transparent
needle.
[0076] The total light transmittance of the resultant needle measured in conformity with
JIS K7105 (1981) "Testing methods for optical properties of plastics" was 80%.
(Manufacturing of acicular body)
[0077] An adhesive tape having an acrylic adhesive layer on the surface of a black polyvinyl
chloride base material was provided as a support plate. The support plate and the
manufactured needle were bonded to each other to form the acicular body of Example
1. In the above adhesive tape, the brightness L* of the surface having the adhesive
layer was 1.5 (measured in conformity with JIS K5600-4-5 (1999) "Testing methods for
paints - Part 4: Visual characteristics of film - Section 5: Colorimetry (Measurement)",
the same applies hereinafter).
(Example 2)
(Manufacturing of intaglio plate)
[0078] The same intaglio plate as that of Example 1 was used.
(Preparation of needle-forming solution)
[0079] Hydroxypropyl cellulose was dissolved in water to prepare 10 wt% hydroxypropyl cellulose
solution as a needle-forming solution.
(Manufacturing of needle)
[0080] A spin coating method was used to fill the recesses of the intaglio plate with the
needle-forming solution. Then, the intaglio plate was heated so that the needle-forming
solution was dried and solidified.
[0081] After the solidifying process, the needle-forming solution which was solidified in
the form of layer was held and removed from the intaglio plate to manufacture a translucent
needle.
[0082] The total light transmittance of the resultant needle measured in conformity with
JIS K7105 (1981) was 30%.
(Manufacturing of acicular body)
[0083] An adhesive tape having an acrylic adhesive layer on the surface of a black polyvinyl
chloride base material was provided as a support plate. The support plate and the
manufactured needle were bonded to each other to provide the acicular body of Example
2. In the above adhesive tape, the brightness L* of the surface having the adhesive
layer was 1.5 (measured in conformity with JIS K5600-4-5 (1999)).
(Example 3)
(Manufacturing of intaglio plate)
[0084] The same intaglio plate as that of Example 1 was used.
(Preparation of needle-forming solution)
[0085] Hydroxypropyl cellulose and model antigen ovalbumin (OVA) were dissolved in water
to prepare 10 wt% hydroxypropyl cellulose solution as a needle-forming solution.
(Manufacturing of needle)
[0086] A spin coating method was used to fill the recesses of the intaglio plate with the
needle-forming solution. Then, the intaglio plate was heated so that the needle-forming
solution was dried and solidified.
[0087] After the solidifying process, the needle-forming solution which was solidified in
the form of layer was held and removed from the intaglio plate to manufacture a translucent
needle.
[0088] The total light transmittance of the resultant needle measured in conformity with
JIS K7105 (1981) was 20%.
(Manufacturing of acicular body)
[0089] An adhesive tape having an acrylic adhesive layer on the surface of a blue polyvinyl
chloride base material was provided as a support plate. The support plate and the
manufactured needle were bonded to each other to provide the acicular body of Example
3. In the above adhesive tape, the brightness L* of the surface having the adhesive
layer was 3.5 (measured in conformity with JIS K5600-4-5 (1999)).
(Example 4)
(Manufacturing of intaglio plate)
[0090] The same intaglio plate as that of Example 1 was used.
(Preparation of needle-forming solution)
[0091] The same needle-forming solution (chitosan succinamide solution) as that of Example
1 was used.
(Manufacturing of needle)
[0092] The needle was formed in the same manner as Example 1.
[0093] The total light transmittance of the resultant needle measured in conformity with
JIS K7105 (1981) was 80%.
(Manufacturing of acicular body)
[0094] An adhesive tape having an acrylic adhesive layer on the surface of a dark brown
polyvinyl chloride base material was provided as a support plate. The support plate
and the manufactured needle were bonded to each other to provide the acicular body
of Example 4. In the above adhesive tape, the brightness L* of the surface having
the adhesive layer was 2.0 (measured in conformity with JIS K5600-4-5 (1999)).
(Example 5)
(Manufacturing of intaglio plate)
[0095] The same intaglio plate as that of Example 1 was used.
(Preparation of needle-forming solution)
[0096] The same needle-forming solution (chitosan succinamide solution) as that of Example
1 was used.
(Manufacturing of needle)
[0097] The needle was formed in the same manner as Example 1.
[0098] The total light transmittance of the resultant needle measured in conformity with
JIS K7105 (1981) was 80%.
(Manufacturing of acicular body)
[0099] An adhesive tape having an acrylic adhesive layer on the surface of a red polyvinyl
chloride base material was provided as a support plate. The support plate and the
manufactured needle were bonded to each other to provide the acicular body of Example
5. In the above adhesive tape, the brightness L* of the surface having the adhesive
layer was 4.5 (measured in conformity with JIS K5600-4-5 (1999)).
(Example 6)
(Manufacturing of intaglio plate)
[0100] The same intaglio plate as that of Example 1 was used.
(Preparation of needle-forming solution)
[0101] The same needle-forming solution (hydroxypropyl cellulose solution) as that of Example
2 was used.
(Manufacturing of needle)
[0102] The needle was formed in the same manner as Example 2.
[0103] The total light transmittance of the resultant needle measured in conformity with
JIS K7105 (1981) was 30%.
(Manufacturing of acicular body)
[0104] An adhesive tape having an acrylic adhesive layer on the surface of a brown polyvinyl
chloride base material was provided as a support plate. The support plate and the
manufactured needle were bonded to each other to provide the acicular body of Example
6. In the above adhesive tape, the brightness L* of the surface having the adhesive
layer was 4.0 (measured in conformity with JIS K5600-4-5 (1999)).
(Example 7)
(Manufacturing of intaglio plate)
[0105] The same intaglio plate as that of Example 1 was used.
(Preparation of needle-forming solution)
[0106] The same needle-forming solution (hydroxypropyl cellulose solution) as that of Example
2 was used.
(Manufacturing of needle)
[0107] The needle was formed in the same manner as Example 2.
[0108] The total light transmittance of the resultant needle measured in conformity with
JIS K7105 (1981) was 30%.
(Manufacturing of acicular body)
[0109] An adhesive tape having an acrylic adhesive layer on the surface of a green polyvinyl
chloride base material was provided as a support plate. The support plate and the
manufactured needle were bonded to each other to provide the acicular body of Example
7. In the above adhesive tape, the brightness L* of the surface having the adhesive
layer was 3.0 (measured in conformity with JIS K5600-4-5 (1999)).
[0110] In Examples 8, 9 and 10, colored needle-forming solution was used to form the base
portion and the support plate of the needle.
(Example 8)
(Manufacturing of intaglio plate)
[0111] The same intaglio plate as that of Example 1 was used.
(Preparation of needle-forming solution (needle))
[0112] The same needle-forming solution (chitosan succinamide solution) as that of Example
1 was used.
(Manufacturing of needle)
[0113] The needle was formed in the same manner as Example 1 by using the needle-forming
solution (needle). In so doing, squeezing was performed after the needle-forming solution
was filled in the recesses of the intaglio plate so that the respective needles were
independently formed. The total light transmittance of the resultant needle measured
in conformity with JIS K7105 (1981) was 85%.
(Preparation of needle-forming solution (support plate))
[0114] Hydroxypropyl cellulose and edible pigment (black) were dissolved in ethanol to prepare
hydroxypropyl cellulose solution with the hydroxypropyl cellulose concentration of
10 wt%.
(Manufacturing of support plate/Manufacturing of acicular body)
[0115] A spin coating method was used to fill the space in the recesses in which the needles
are formed with the needle-forming solution (support plate). Then, the needle-forming
solution was further supplied to such an extent that a layer was formed on the intaglio
plate. The intaglio plate was heated at a temperature of 120°C for a period of 10
minutes by using a heat source so that the needle-forming solution (support plate)
was dried and solidified. A hotplate was used as the heat source.
[0116] After the solidifying process, the needle-forming solution which was solidified in
the form of layer was held and removed from the intaglio plate to manufacture a two-layered
acicular body having the support plate and the needle made of the needle-forming solution.
[0117] The brightness L* of the support plate was 1.5 (measured in conformity with JIS K5600-4-5
(1999)).
(Example 9)
(Manufacturing of intaglio plate)
[0118] The same intaglio plate as that of Example 2 was used.
(Preparation of needle-forming solution (needle))
[0119] The same needle-forming solution (hydroxypropyl cellulose solution) as that of Example
2 was used.
(Manufacturing of needle)
[0120] The needle was formed in the same manner as Example 8. The total light transmittance
of the resultant needle measured in conformity with JIS K7105 (1981) was 40%.
(Preparation of needle-forming solution (support plate))
[0121] Pullulan and edible pigment (black) were dissolved in hot water at 45°C to prepare
pullulan solution with the pullulan concentration of 10 wt% as a needle-forming solution
(support plate).
(Manufacturing of support plate/Manufacturing of acicular body)
[0122] A spin coating method was used to fill the space in the recesses in which the needles
are formed with the needle-forming solution (support plate). Then, the needle-forming
solution was further supplied to such an extent that a layer was formed on the intaglio
plate. The intaglio plate was heated by using a heat source so that the needle-forming
solution (support plate) was dried and solidified.
[0123] After the solidifying process, the needle-forming solution which was solidified in
the form of layer was held and removed from the intaglio plate to manufacture a two-layered
acicular body having the support plate and the needle made of the needle-forming solution.
[0124] The brightness L* of the support plate was 1.5 (measured in conformity with JIS K5600-4-5
(1999)).
(Example 10)
(Manufacturing of intaglio plate)
[0125] The same intaglio plate as that of Example 1 was used.
(Preparation of needle-forming solution (needle))
[0126] The same needle-forming solution (chitosan succinamide solution) as that of Example
1 was used.
(Manufacturing of needle)
[0127] The needle was formed in the same manner as Example 8. The total light transmittance
of the resultant needle measured in conformity with JIS K7105 (1981) was 85%.
(Preparation of needle-forming solution (support plate))
[0128] Hydroxypropyl cellulose and methylene blue (blue pigment) were dissolved in ethanol
to prepare hydroxypropyl cellulose solution with the hydroxypropyl cellulose concentration
of 10 wt%.
(Manufacturing of support plate/Manufacturing of acicular body)
[0129] A two-layered acicular body having the support plate and the needle made of the needle-forming
solution (support plate) was manufactured in the same manner as Example 8.
[0130] The brightness L* of the support plate was 4.0 (measured in conformity with JIS K5600-4-5
(1999)).
(Comparative example 1)
(Manufacturing of intaglio plate)
[0131] The same intaglio plate as that of Example 1 was used.
(Preparation of needle-forming solution)
[0132] The same needle-forming solution (chitosan succinamide solution) as that of Example
1 was used.
(Manufacturing of needle)
[0133] The needle was formed in the same manner as Example 1. The total light transmittance
of the resultant needle measured in conformity with JIS K7105 (1981) was 80%.
(Manufacturing of acicular body)
[0134] An adhesive tape having an acrylic adhesive layer on the surface of a white polyvinyl
chloride base material was provided as a support plate. The support plate and the
manufactured needle were bonded to each other to provide the acicular body of Comparative
example 1. In the above adhesive tape, the brightness L* of the surface having the
adhesive layer was 9.0 (measured in conformity with JIS K5600-4-5 (1999)).
(Comparative example 2)
(Manufacturing of intaglio plate)
[0135] The same intaglio plate as that of Example 1 was used.
(Preparation of needle-forming solution (needle))
[0136] The same needle-forming solution (chitosan succinamide solution) as that of Example
1 was used.
(Manufacturing of needle)
[0137] The needle was formed in the same manner as Example 8. The total light transmittance
of the resultant needle measured in conformity with JIS K7105 (1981) was 85%.
(Preparation of needle-forming solution (support plate))
[0138] Hydroxypropyl cellulose and edible pigment (white) were dissolved in ethanol to prepare
the solution with the hydroxypropyl cellulose concentration of 10 wt% as a needle-forming
solution (support plate).
(Manufacturing of support plate/Manufacturing of acicular body)
[0139] A two-layered acicular body having the support plate and the needle made of the needle-forming
solution (support plate) was manufactured in the same manner as Example 8.
[0140] The brightness L* of the support plate was 9.0 (measured in conformity with JIS K5600-4-5
(1999)).
(Evaluation 1)
[0141] The acicular bodies of the Examples and Comparative examples were visually observed
from a position on the needle-side with the needle overlapping the support plate.
[0142] In Examples 1 to 10, the needles were clearly visually observed. Further, the tips
of the needles were visually observed as bright spots. In Comparative examples 1 and
2, the needles were not visually observed due to visible light reflection of the support
plate.
(Evaluation 2)
[0143] The needles of the acicular bodies of the Examples and Comparative examples were
peeled off from the artificial skin 10 minutes after the piercing and were visually
observed from the same point as that of Evaluation 1.
[0144] In Examples 1 to 10, the bright spots, which were observed in Evaluation 1, were
not observed. This revealed that the tips of the needles were dissolved. In Comparative
examples 1 and 2, whether or not the tips of the needles were dissolved was not confirmed.
[0145] Fig. 9 shows a microscope image of the acicular body according to Example 1 taken
from the needle-side. Fig. 10 shows a microscope image of the acicular body of Comparative
example 2 taken under the same condition as Fig. 9. In Figs. 9 and 10, the needle
is located within an area D surrounded by the dotted line. While the position of the
needle was readily confirmed by visual observation in Fig. 9, the needle was not readily
confirmed in Fig. 10.
[0146] Although the embodiments and examples of the present invention have been described,
the technical scope of the present invention is not limited to those embodiments,
and combinations of the components may be varied and various modifications and deletions
can be made to the components without departing from the teachings of the present
invention.
Reference Signs List
[0147]
- 1
- acicular body
- 10, 11, 40, 60
- support plate
- 10b
- projection
- 20
- needle
- 20a
- tip
- 20b
- base portion (needle)
- 20c
- light transmission area
- 12
- adhesive layer
- 50
- base material tape